Rare Earth Complexes With Four Isopropyl Methylene Phosphonate Synthesis, Structure And Nature Of The Study

Trivalence rare earth ions are Lewis hard acid and are very oxophilic, they are expected to interact strongly with highly polarized O-bearing functional groups such as ligands involving phosphoryl (P=O) group to form a number of complexes and polymers, which have not only a variety of structures but also special magnetic, electric and optical properties. Therefore, they can be extensively used in many fields such as petrochemistry, fluorescence materials, biological materials, polymer materials, and catalyst in specific organic reactions and so on. The synthesis, structures and catalysis properties of rare earth complexes and polymers with diphosphonate have been recently attracted.The NO₃- ions in the lanthanide nitrates are chelating bidentate ligand, which enable the bidentate diphosphonate ligand to form crystal complexes with a great number of literatures, while Cl- ions in lanthanide chloride are monodentate ligand with low activity, so complexes crystals are not so easy to be formed, and there are few relative literatures.In this paper, tetraisopropylmethylenediphosphonate(=L) is chosen as main ligand, phen (1,10-phenanthroline) as a auxiliary ligand, three novel lanthanide complexes containing chloride ions, [LaClL₂(H₂O)₄]·Cl₂(1) , [CeClL₂(H₂O)₄]·Cl₂ (₂) , and [CeCl₃(phen)₂(DMF)]·(DMF) (₃) have been synthesized and characterized. Using Ce/Cl/L complexes as catalys, MBT, MBTS are synthesized in solvent C₂H5OH and a postulated mechanism has been proposed.In addition, the crystals of other four new complexes are also obtained, [DyL₄]·(OTf)·(DMF) (4), [La(NO₃)₃L₂](5), [Ce(NO₃)₃L₂] (6) and [Nd(NO₃)₃L₂](7), suitable crystals are selected to be characterized by element analysis, infrared spectra, 1H NMR, ₃1P NMR, luminescence spectra and X-ray single crystal diffraction.